Explosive initiating devices generally employ an explosive train wherein a number of explosive components are arranged in tandem from the very sensitive to very insensitive. The sensitive explosive initiator components can be activated from a very small electrical or mechanical stimulus. The most common initiating devices presently employed in explosives detonation employ sensitive primary explosive initiator components such as lead azide or lead styphnate. In an explosive train, the output from one of these very sensitive explosives then activates explosives which are less sensitive and therefore safer to handle.
The explosive components in an explosive train are arranged from the very sensitive to very insensitive with the most sensitive components being the smaller amounts and the least sensitive being the main charge. The primary disadvantage of initiating devices containing lead azide or lead styphnate is that these sensitive explosives can be accidentally detonated if exposed to shock or static electricity. Other disadvantages imposed by the sensitive nature of these initiators include the requirements for special handling, storage, and transportation. There is thus a definite need in the art for less sensitive explosive initiators that retain the reliability of the sensitive lead azide and lead styphnate based initiators.
A primary explosive is an explosive with sensitivity such that a small amount of explosive (less than one gram) can be detonated by means of a nonexplosive stimulus such as flame, spark, heat, or impact. Primary explosives are required to be sensitive to detonation by at least one of these types of stimuli. It is also possible that a particular explosive can be detonated by flame, but is insensitive to detonation by impact.
Accordingly, it is an object of the present invention to provide explosive initiating devices containing a reliable primary explosive that is less sensitive to initiation by impact and static electricity than commonly-used materials such as lead azide and lead styphnate.
Another object of the present invention is to provide a shock insensitive primary component for an explosive train employed in an explosive initiator.
A further object of the present invention is to provide a new and novel insensitive primary explosive component for an initiating device.